Such a method is known from U.S. Pat. Nos. 5,366,140 and 5,486,427, in which a substrate is provided with a metal layer which is partitioned into metal regions, and is subsequently heated in an oven to a temperature sufficient to melt the metal and permit beading of the layer into discrete metal droplets. When subsequently allowed to cool, the resulting metal microbeads (solidified droplets) are removed from the substrate by scraping or brushing, so that they can be collected in a container for later use. The micro-beads typically have a diameter of the order of 1 to 50 .mu.m.
An important possible use for such microbeads is, for example, in the creation of connector bumps on integrated circuits and miniature surface-mountable electrical components. However, a considerable problem with such applications is the accurate positioning of individual microbeads on the extremities of such tiny components, and the subsequent fixation of the positioned microbeads to the target area (e.g. using a holding-melting-cooling procedure). In practice, this task is either tediously time-consuming, and thus costly, or has such a high fall-out percentage as to make it commercially unattractive.
A considerable disadvantage of the known method is the fact that it contains relatively many process steps (substrate manufacture, heating in oven, cooling, mechanical removal and collection of microbeads, placement of microbeads in final application). In addition, abrasive removal of the microbeads from the substrate (by scraping or brushing) can be tedious, and can easily damage the microbeads, especially when they are comprised of a soft metal (such as a Pb-Sn alloy, for example).